Refining apparatus



June 10, '1969 F. c. VAUGHAN 3, 4

REFINING APPARA TUS Filed Aug. 12, 1966 JNVENTOR.

FRANK c. VAUGHAN I d ZfiM ATTORNEYS United States Patent Office3,448,934 Patented June 10, 1969 3,448,934 REFINING APPARATUS Frank C.Vaughan, 103 W. Brookland Park Blvd., Richmond, Va. 23222 Filed Aug. 12,1966, Ser. No. 572,066 Int. Cl. B02c 7/02, 7/14, 23/00 US. Cl. 241-146 6Claims ABSTRACT OF THE DISCLOSURE The present invention relates torefining apparatus and more particularly to refining apparatus for papermaking stock of the single rotor type, usually double-faced. Theapparatus of the present invention while having primary utility in thefield of paper stock refining, will nevertheless have utility for therefining of other materials, the only limitation being that the materialto be refined must flow readily as a slurry or the like. Thus, while thedescription which follows hereinafter will be directed primarily to asingle rotor double-faced paper stock refining apparatus, it is to beunderstood that the basic principles involved are capable ofsubstantially broader application.

There is nothing broadly new in the use of single rotor double-facedrefiners for paper stock and, in fact, such apparatus in one form oranother is in very widespread use throughout the paper-making industryand the art pertaining to machines of this type may fairly be said to behighly developed. Apparatus of this type all basically include within aclosed housing defining a refining chamber, a rotor member carryingrefining plates or abrading surfaces on opposite radial faces thereof.Sets of non-rotating plates or abrading surfaces which cooperate withthose carried by the rotor are supported within the housing, parallel tothe rotor surfaces and in close proximity thereto. In general, stock tobe refined is fed to the inner radial ends of the cooperating abradingsurfaces and proceeds radially outwardly during the refining process.For a great number of years, the prior art machines of this type haveincluded a means for supporting the non-rotating plates in a very rigidmanner, the theory being that there should be exact parallelism betweenthe adjacent abrading surfaces. Most of the commercial machines includea means for varying the spacing between adjacent abrading surfaceswithout destroying the concentricity or parallel relationshiptherebetween. Obviously, due to problems in machining, tolerances, wear,parts deformation, and the like, it is a very difiicult thing to secureand/or maintain the desired relationship between the abrading surfacesduring operation of the machine and the larger the size of the machine,the more acute this problem becomes. This has led to rather massivestructures for adjustment of the non-rotating abrading surfaces andother problems which occur including maintaining fluid-tight sealsthrough the adjusting mechanism. In spite of all precautions which havebeen taken, machines of this type all suffer from one or more of thefollowing defects:

(1) The rotor or runner may have wobble due to inaccuracies of machiningor of the assmbly or plates.

(2) Due to varying temperature distribution or use of dissimilar metals,there may be a differential expansion of the bearing supports causingmisalignment.

(3) After the machine has been in operation for a period of time, theremay be uneven and unequal wear on" the plates, and/or other parts.

(4) There may be deflections and distortions of any one of a number ofthe machine parts which vary continually during operation of the machineand which therefore produce misalignment of the paired refining plates.

(5) As most existing refiners of this general design employ slidingseals or packing to keep the housing or refining chamber pressure-tight,the force required to move, the non-rotating head or heads must overcomea fbreakaway friction initially and this causes hunting or makespractically impossible minute adjustments of loading pressure or headposition. Thus, sensitivity to control demands is poor.

.;-The apparatus of the present invention represents a very markeddeparture from structures previously proposed for this purpose. Inaccordance with the present invention, the non-rotating refining platesare resiliently rather than rigidly mounted within the housing so thatthey have a limited range of axial movement toward and away from therotary refining plates and limited ability to align themselvespermanently or cyclically to the rotating plates. It has been found thatby utilizing such a resilient support, that substantially all of theforegoing disadvantages of the prior art apparatus are overcome. Inaddition, the overall size and weight of the apparatus for a givenrefining through-put is substantially reduced together with thecomplexity of the machine as a whole due to the elimination ofadjustment, structure and the related rotary seals and the like.

Accordingly, it is the principal object of the present invention toprovide in a single rotor double-faced paper pulp refining apparatus, aresilient supporting means for the non-rotating refining plates.

A further object of the present invention is to provide means for urgingthe non-rotating plates toward the rotary plates by means of fluidpressure applied between the interior of the housing and thenon-rotating plates.

A still further object of the present invention is to provide a novelmeans for mounting a rotor member on the machine shaft.

Other objects will be apparent to those skilled in the art from aconsideration of the following detailed description taken in conjunctionwith the attached sheet of drawings in which:

FIG. 1 shows a side elevation partially in section of a preferredembodiment of the present invention;

FIG. 2 is an enlarged view of one of the resilient mountings shown inFIG. 1; and

FIG. 3 is also an enlarged view of a portion of FIG. 1 showing detailsof the connection between the outboard and inboard heads whichfacilitates disassembly andreassembly of the entire refiner.

In general, the objects of the present invention are achieved byproviding a support for the non-rotating plates of the single rotordouble-faced refiner which support is resilient and which resilientlyconnects the inner and outer periphery of the refining plates to thehousing defining the refining chamber, all points of connection beingfiuid tight. Additionally, a fluid pressure supply line extends throughthe heads of the machine and into the space between the interior of thehousing and the refining plates in order to provide a means for urgingthe non-rotating plates axially toward the rotating plates carried bythe machine rotor.

Referring now to the single sheet of drawings, the main shaft of themachine is indicated at '10 and the housing-within which the refiningplates are mounted is shown generally at 12. The housing 12 includesinboard and outboard heads 14 and 16, respectively. The annular areabetween the inboard and outboard heads 3 houses the refiner proper andtherefore defines the refining chamber. The basic element of the refineris the rotor 18 carried by the shaft 10. The annular rotary refiningplates 20 and 22 which are entirely conventional in this art are boltedor otherwise rigidly attached to opposite radial faces of the rotor 18.

The non-rotating plates which cooperate with plates 20 and 22 carried bythe rotor are shown at 24 and 26. These plates are also annular and arerigidly attached to inboard and outboard carrier plates 28 and 30,respectively.

The heart of the present invention lies in the manner of supportingthese carrier plates resiliently and in fluidtight relationship with theinterior of the housing. In order to accomplish this result, a pair ofannular diaphragms of flexible material are employed for each carrierplate. The outer inboard diaphragm is shown at 32 and the outer outboarddiaphragm at 34. The outer peripheries of the diaphragms 32 and 34 areclamped to the inner surfaces of the inboard and outboard heads 14 and16, respectively, by means of clamping rings 36 and 38 which are simplybolted to the inboard and outboard heads. The inner edges of diaphragms32 and 34 are clamped respectively to carrier plates 28 and 30 by meansof clamping rings 40 and 42 which are bolted to the carrier plates 28and 30. The inner inboard and outboard diaphragms are shown respectivelyat 44 and 46. Conveniently, these diaphragms are U-shape in crosssectionas shown in the drawing and the legs of the U are simply bolted to thecarrier plate and to the head. With this structure, it will be seen thata fluid-tight annular chamber between each head and its respectivecarrier plate is thus created. The annular rings 47 and 49 positionedbetween the legs of the U prevent collapse and possible damage to thediaphragms 47 and 49 due to the existence of a higher housing pressureat the inner end of the refining chamber than the fluid loading pressurebetween the plates and the heads of the machine which may occur duringstart ups and shut downs. The carrier plates therefor together withtheir respective refining plates are free to move within a limited rangeof axial movement toward and away from the rotary refining platescarried by the rotor, and at the same time the support means carries theweight of and prevents rotation of the non-rotating plates. Suchsuspension permits practically friction-free axial motion of thenonrotating plates and further permits aligning of the nonrotating tothe rotating plates.

Only the outer diaphragms 32 and 34 need have the capacity forsupporting the weight of the plates and be sufliciently strong intorsion to prevent rotation of the plates 24 and 26 although conceivablyboth inner and outer diaphragms could so function or the inner diaphragmcould so function alone.

As shown in the drawings, the carrier plates 28 and 30 are in theirfully retracted positions, that is, the position corresponding tomaximum clearance between the rotary and non-rotating refining plates.The carriers are normally biased toward this position by a plurality ofspring devices generally indicated by the reference numeral 48.Preferably, there are three or more such spring biasing assemblies foreach carrier plate and they are spaced at appropriate intervalscircumferentially of each plate. Only one such device is shown in FIG.1, but it will be understood that there are preferably three or more foreach of the inboard and outboard non-rotating plates.

In order to urge the non-rotating carrier plates toward the rotor andthus reduce the clearance between the respective cooperating refiningplate pairs, means are provided for injecting fluid under pressure intothe annular space between the carrier plates and their respectivemachine heads. Such means is shown in FIG. 1 as a pair of fluid pressurefittings 50 and 52 on the inboard and outboard heads, respectively.These fittings are joined by a common conduit 54 connected to a sourceof pressure not shown.

Turning now to the rotor 18 and the means for attaching the rotor to theshaft 10 for access to change plates and for other maintenancefunctions, it is obviously desirable to have the rotor removably butrigidly affixed to the shaft by means which on each disassembly andreassembly are easily capable of accurately reproducing the originalmounting alignment. To achieve this result, a hub 54 is keyed orotherwise rigidly attached to a cylindrical portion of the shaft 10. Thecentral portion of the hub 54 is welded or otherwise rigidly secured tothe disc of the rotor 18. The outer portions 56 and 58 of the hub 54each taper outwardly to form conical surfaces. The rotor is aligned onthe hub and the entire assembly is clamped on the shaft by means of apair of clamping rings 60 and 62 which have inner conical surfacesmating with the tapering surfaces of the hub 54. A clamping means shownin the drawing as a bolt 64 is used to draw the rings 60 and 62 towardeach other and toward the rotor bolt assembly with their conicalsurfaces in engagement with the conical surfaces of the hub.

Still another feature of the present invention is the fact that theshaft 10 is fixed axially and therefore does not move axially in thepacking gland which is indicated generally by reference numeral 66. Thestructure of this packing gland is such that the packing may beadjusted, added to, or replaced from either the interior or the exteriorof the refiner housing.

The main stock inlet for the material to be refined is shown at 68 andit will be noted that the inlet 68 connects with a pair of conduits 70and 72 which lead to opposite sides of the rotor 18 adjacent the innerradial ends of the refining plates. In order to facilitate disassemblyand reassembly of the refiner, it will be noted that the conduit 72which connects with the stock inlet 68 for conveying stock to be refinedto the outboard side of the refiner is rigidly attached to the removableouter head and is connected with a telescopic joint sealed with a ringof elastomeric material having a lip portion which is deflected radiallyoutwardly upon insertion of the conduit 72 therethrough. On disassemblyof the outer head from the inner head, the stock conduit 72 may merelybe slid outwardly of the sealing assembly, without removal of any boltsor other fastening devices.

Referring to FIG. 3, it will be seen that the outboard head through theflange 75 is secured to the inboard head by a ring member 74 receivedwithin a groove 76 in the flange 75. Once the flange 75 has beenpositioned so that the groove 76 clears the inboard head, the ring 74 ismerely inserted and it can then be clamped in place by a ring ofclamping studs, one of which is shown at 78.

A stock outlet similar to the stock inlet is also provided but does notappear in the drawings since it is positioned behind the inlet but ithas the same tyne of telescoping connection as the inlet conduit 72.

It will be understood that the inboard head is rigidly attached to themachine base which also supports the bearing for the shaft 10 and thatthe head is mounted so as to be accurately positioned normal to the axisof the shaft 10.

To facilitate disassembly of the machine for maintenance or otherreasons, the outboard head is secured to the inboard head by means ofthe annular ring 74 which snaps into the groove 76. Clamping screws 78hold the ring in place and removal of these screws permits removal ofthe ring. The outboard head may then be removed and the stock inletcomes olf with it as well as the stock outlet.

All parts will be made of materials best suited to mechanics of thedesign except that all surfaces exposed to wetting by process liquids,vapors, splashes, drips, etc., will be made of, faced with, or linedwith a non-corrosive metal or alloy, usually one of the stainlesssteels.

From the foregoing description, it will be apparent to those skilled inthis art that there is herein shown and disclosed a new and usefulrefining apparatus. It is contemplated that the flexible mounting of thenon-rotating refiner plates will markedly reduce the operating soundlevel of the refiner in addition to permitting effectively an automaticalignment of the rotating and non-rotating plates to compensate for allpossible manufacturing and machining inaccuracies.

While the machine has been described particularly with respect torefining surfaces of a planar nature, it will be further apparent tothose skilled in the art that the invention is not in fact so limitedand that the broad principles are equally applicable to machines havingrefining surfaces of conical or partial conical or partial sphericalnature, or combinations of both. In fact, the only apparent limitationis that the refining surfaces are revolved relative to each other and inclose proximity to each other.

Thus while a preferred embodiment has been herein shown and described,it will be further apparent to those skilled in the art that there willbe many mechanical equivalents and variations and accordingly applicantclaims the benefit of a full range of mechanical equivalents within thescope of the appended claims.

I claim:

1. Apparatus for refining paper pulp or other flowable slurriescomprising:

a housing;

a rotor mounted within said housing and having at least one refiningplate rigidly atfixed thereto;

at least one non-rotating refining plate cooperating with said rotorrefining plate;

means mounting said non-rotating plate within said housing influid-tight relation thereto and substantially concentrically with saidrotor, said means preventing rotation of said plate relative to saidhousing but permitting limited axial movement of said plate toward andaway from said rotor and further permitting movement of saidnon-rotating plate to align itself concentrically with and in parallelrelation to said refining plate mounted on said rotor;

and means for supplying fluid under pressure between the interior ofsaid housing and said non-rotating plate to urge said plate axiallytoward said rotor, said fluid being under pressure from a source whichis independent of any pressure developed internally of said housing.

2. The combination defined by claim 1 and further including meansnormally biasing said non-rotating plate axially away from said rotor.

3. A single rotor double faced paper pulp refining aoparatus comprising:

a housing;

a rotor mounted within said housing and having refining plates rigidlyaffixed to each radial face thereof;

non-rotating annular refining plates cooperating with said rotorrefining plates;

means mounting said non-rotating refining plates within said housing influid-tight relation thereto, substantially concentric with said rotor,said means preventing rotation of said plates with respect to saidhousing but permitting limited axial movement toward and away from saidrotor and further permitting said non-rotating plates to alignthemselves concentrically with and in parallel relation to said refiningplates mounted on said rotor;

and means for supplying fluid under pressure between the interior ofsaid housing and said non-rotating plates to urge said plates axiallytoward said rotor, said fluid being under pressure from a source whichis independent of any pressure developed internally of said housing.

4. The combination defined by claim 3 and including means normallybiasing said non-rotating plates axially away from said rotor.

5. A single rotor double faced paper pulp refining apparatus comprising:

a housing;

a rotor mounted within said housing and having refining plates rigidlyafiixed to each radial face thereof;

non-rotating annular refining plates cooperating with said rotorrefining plates;

means supporting said non-rotating plates on the interior of saidhousing, said means including inner and outer annular members offlexible material having one peripheral portion attached to said housingand the other peripheral portion attached to said plates, both influid-tight relation whereby said non-rotating plates have a limitedfreedom of axial movement toward and away from said rotor and acapability of aligning themselves concentrically and in parallelrelation to said refining plates carried by said rotor;

and means for supplying fluid under pressure between the interior ofsaid housing and said non-rotating plates to urge said plates axiallytoward said rotor, said fluid being under pressure from a source whichis independent of any pressure developed internally of said housing.

6. The combination defined by claim 5 and including means normallybiasing said non-rotating plates axially away from said rotor.

References Cited UNITED STATES PATENTS 2,156,320 5/1939 Sutherland241-255 X 2,566,949 9/1951 Marco 24l-146 X 3,323,731 6/1967 Asplund etal. 241146 3,371,873 3/1968 Thomas 241-146 X ANDREW R. JUHASZ, PrimaryExaminer.

US. Cl. X.R. 241-290

